Record disk



.F. LENTON.

RECORD DISK.

APPLICATION FILED MM} 9, i921.

1,417,339, Patented May 23, 1922.

IiYIIIIIIIlVll/IIIIIIIIIIIIIIIIIII!IIIIIII/IlllllqllllllI/ (IJIIIIIIAWITNESSES INVENTOH 4 TTOHNEYS RECORD DISK.

Specification of Letters Patent.

Patented May 23, 1922.

Application filed March 9, 1921. Serial No. 451,063.

To all whom it may concern Be it known that l, F uni; LENroN, a subjectof the King of Great Britain, and a resident of the city of New York,(borough of Manhattan), in the county of New York and State of New York,have invented a new and Improved Record. Disk, of which the follow ingis a full clear and exact description.

This invention relates to improvements in disk records for qraphophones,and seeks for its principal object to provide a simple and inexpensivemeans for facilitating the application of the record to the turn-tableor revolving platform of the machine.

A further object of the invention resides in the production of a recordprovided with means of the character described which insures the propercentering of the record in order that the center of rotation thereofwill coincide with the center of rotation of the turn-table or revolvingplatform.

It is a further object of the invention to produce a record of thecharacter described which does not add to the expense of manufacture andwhich does not necessitate any alteration to the graphophone proper.

l i ith the above recited and other objects in view, some of which willappear hereafter as the 1.1ature purpose and operation of the inventionis more fully understood, reference is had to the followingspecification, the appended claims, and the accompanying drawings, inwhich;

Figure 1 is a plan view of a record disk constructed in accordance withthe invention.

Figure 2 is a transverse sectional view therethrough taken approximatelyon the line 2-2 of Figure 1.

Figure 3 is a fragmentary plan view illustrating a modified form inwhich the opening may be made.

Figure at is similar view of a further modification Referring to thecrawings by characters of reference, 10 designates a record disk havingthe usual centrally disposed portion 11 around which the spirallyarranged sound reproducing grooves 12 are disposed. In the common formof records a centrally or axially disposed centering opening is providedwhich is designed to co-act with the centering pin provided on the turntable or revolving platform of the graphophone. By this method a greatdeal of difficulty is experienced and unnecessary delay is occasioned inthe registering of the centering opening with the centering pin. Inorder to obviate this di'fiiculty a. sector-like opening 13 is formed inthe central portion, the same being provided with converging side wallsi l which connect with a semi-circular end wall 15 the radius of whichis struck from a center substantially coincident to the center ofrevolution of the record. The radius of said semi-circular wall issubstantially equal to the radius of the centering pin provided on theturn table of the graphophone. The outer end wall 16 may be of arcuateor any other suitable formation depending on the fancy of themanufacturer. By this arrangement it is obvious that the opening 13 willafford a clear viewing space through which the centering pin of thegraphophone will be visible in placing the record on the machine, henthe record is placed on the turn table with the opening 13 arranged overthe centering pin, it is only necessary to push the record in a generaldirection to advance the inner end of the opening toward the centering;pin, Either one of the converging side walls 14 will function toproperly guide the record to a centered position where it will beretained by the frictional contact of the under surface of the recordwith the turn table. The maximum speed. at which the revolving platformsor turn tables of graphophones are now rotated is not sufficient toeffect displacement of the record through centrifugal force but in eventof a substantial increase in the speed of rotation it is pos sible todispose the semi-circular inner end wall. slightly eccentric to equalizethe weight on the opposite sides of the center of rotation to precludeany possibility of centrifugal force displacing the record.

In the modified form illustrated in Figure 3 of the drawings, theconverging side walls 1 of the opening 13 are arranged at atangent tothe arcuate inner end wall 15 In this instance the use and operation ofthe opening a a means for facilitating the centering of the record isidentical with that described in the preferred embodiment.

In the modification illustrated in FlgUIB i of the drawings, the opening13* is sectorshape, the converging side walls 14; thereof connectingwith each other at a point eccentric to the center of revolution of therecord. The center of the record will coincide with the center ofrotation of the pin 17.

From the foregoing it will be seen that an extremely simple andinexpensive means for facilitating the application of the record to theturn table is provided, which comprises an opening in the record, theinner end of which co-acts with the centering pin to cause the center ofrotation of the record to coincide with the center of rotation of theturntable.

While there has been illustrated and described several preferred shapesin which the opening may be formed, no limitation is necessarily madethereto as it is to be understood that the right is reserved tomodifications or embodiments other than those set forth, to the fullestextent indicated by thegeneral meaning of the terms in which the claimsare expressed and by variations in the phraseology of the same.

I claim:

1. As a new article of manufacture, a sound reproducing record diskprovided with an opening therethrough having a pin receiving portion atits inner end located at the center of the record disk and constitutingmeans adapted for engagement with the centering pin of a graphophoneturntable to effect the coincidence of the center of rotation of therecord with the center of rotation having a restricted end disposed atthe cen- V ter or axis of the record to constitute a receiving portionfor the centering pin of a graphophone turntable'whereby to effect thecoincidence of the center of rotation of the record with the center ofrotation of the turntable.

3. As a new article of manufacture, a phonograph disk record having acentral pin receiving portion and a relatively wide opening connectingtherewith, two walls of said opening converging to said :pin re ceivingportions.

4. As an article of manufacture, a sound reproducing record disk havingan opening extending therethrough, one end of said opening beingdisposed at the axial center of said disk toconstitute a receivingportion adapted for engagement with the centering pin, the remainder ofsaid opening serving as a means for visualizing the pin to facilitatethe'application of the record to the turntable.

FRANK LENTON.

